The Thirty Meter Telescope (TMT) could take up residence in Spain’s Canary Islands, instead of its proposed location of Hawaii, after difficult legal battles and protests have ground construction to a halt.

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The TMT is the largest in a series of extremely large ground-based telescopes (ELTS) and will be part of a new astronomical observatory set to cost around $1.8 billion (£1.4 bn) to build. It is intended to carry out optical and infrared astronomy and will help astronomers discover the properties of the Universe, as well as answer questions such as 'what is the origin of life'.

The telescope will stand 18 storeys tall with a 98-foot-wide primary mirror inside. Once built, the TMT will be one of the largest optical-light observatory ever, second the to the E-ELT, the European Extremely Large Telescope.

A committee settled on constructing the TMT on the summit of the dormant volcano Manua Kea, in Hawaii, 14,000ft above sea level. The site was chosen because it has good atmospheric turbulence properties to offer scientists sharp views of the distant Universe.

However, Hawaiians are unhappy with the proposals. Mauna Kea is seen as the most sacred mountain in Hawaiian culture and since 2014, the “mountain protectors” have objected to the construction of the TMT, through protests and lawsuits. Last year, the Hawaii Supreme Court blocked the construction of the telescope completely.

As a result, the TMT International Observatory Board of Governors (TIO) has settled on moving the TMT project to the island of La Palma. It is considered the second best location for optical and infrared astronomy in the northern hemisphere after Mauna Kea, but there are drawbacks.

As La Palma’s proposed location isn’t as high above sea level as Mauna Kea, the work of the astronomers would be affected by more interference from Earth’s atmosphere. This would reduce the scope’s resolution, and in particular affect the mid-infrared wavelengths needed to observe galactic centres.

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Despite seeking an alternative site, the board still has its sights set on Hawaii. "Mauna Kea continues to be the preferred choice for the location of the Thirty Meter Telescope, and the TIO Board will continue intensive efforts to gain approval for TMT in Hawaii,” said Henry Yang, chair of TIO’s Board, in a statement.

TIO’s Board has said that regardless of what happens, construction of the TMT will begin no later than April 2018.